Forklift Fuel Cell Supply System

ABSTRACT

This invention provides a forklift fuel cell supply system consists of enclosure  90  and the fuel cell system  100 , DCDC converting unit  2 , contactor  3 , energy storage device  4 , controller  7  provided in the said enclosure  90 , which also consists of the power supply output end  5  provided outside the said enclosure  90  and the operation control unit  6  provided in the said enclosure  90 , in which the said contactor  3  is a normal open type high-current contactor, the said DCDC converting unit  2  includes the DCDC converter  21  and high-power diode  22  connecting with it. This invention is compact in structure and facilitates such work as system installation, overhaul and maintenance, etc. This invention can contain an energy storage device with a higher capacity, making the energy storage device be in a charging and discharging condition with a low multiplying factor and extending the service life of the energy storage device and the time for which the system can be left unused.

PRIORITY

The present invention claims priority to U.S. patent application Ser.No. 14/366,011 which claims priority to PCT patent applicationPCT/CN2013/083379, which has a filing date of Sep. 12, 2013 and claimspriority to Chinese patent application 201210376341, which has a filingdate of Sep. 28, 2012.

FIELD OF THE INVENTION

This invention relates to the new energy field, specifically to aforklift fuel cell supply system.

BACKGROUND

When designing a forklift fuel cell system, in order to replace with theexisting lead-acid battery directly to avoid forklift modification, allparts and components have to be centralized in a rectangular emptychamber. The forklift fuel cell system needs to include controller,energy storage device, DCDC converter, contactor, fuel cell system,hydrogen filling valve, hydrogen bottle, hydrogen system, etc. In orderfor the system to reach a weight equal to that of lead-acid battery,weights have to be placed. The parts and components required by thewhole system are integrated in a narrow space, resulting in space beingnot available between parts and components. This may bring a very hightrouble to installation, disassembly. Even when disassembling some partsand components, other parts and components have to be removed first.

The existing technology has a lot of disadvantages. Some design reducessystem function; some design adopts an energy storage device with asmall size and a small capacity, resulting in reduction in systemperformance; some design even has the hydrogen bottle be placed outsidethe system; some design provides almost no space for moving betweenparts and components in the system, as a result, when disassembling apart and component, other parts and components have to be removed; somedesign has no space in the system for the emergency stop button andrelies on the emergency stop button designed for the hydrogen fillingsystem, this may result in being unable to close the system quicklyunder an exceptional system emergency condition.

The technical scheme publicized by the utility model patent of Chinacalled “forklift gas bottle fixing device” with application number“200820233706.2” has the gas bottle be placed at the back end of aforklift, when using, it is necessary to change the hydrogen bottle,this also needs a lot of time. At the same time, placing a gas bottle atback of a forklift is very unsafe. Due to system being not compact, thatscheme is unable to place the hydrogen bottle inside the system.

The Canadian patent called “FUEL CELL INDUSTRIAL VEHICLE” withpublication number “CA2659135A1” provides a fuel cell forklift systemscheme and redesigns the whole forklift. No direct replacement of theexisting forklift cell can be made.

The utility model patent of China called “a new type of forklift” withapplication number “200920174236.1” provides a technical scheme whichalso considers redesign of existing vehicle.

The utility model patent of China called “a type of fuel cell forklift”with application number “200820179687.X” provides a technical schemewhich also considers forklift redesign.

SUMMARY

Aimed at the defects in existing technology, the said improved forkliftfuel cell supply system solves the compact problem with the forkliftfuel cell system. The forklift fuel cell has the whole system be placedin a rectangular empty chamber. Due to dimensional limitation, there isalmost no space for moving between the parts and components. The lineinstallation is troublesome. Disassembly of parts and components aretroublesome with other parts and components having to be removed first.A space for weights is reserved.

The said forklift fuel cell supply system consists of enclosure and thefuel cell system, DCDC converting unit, contactor, energy storagedevice, controller provided in the said enclosure, which also consistsof the power supply output end provided outside the said enclosure andthe operation control unit 6 provided in the said enclosure, in whichthe said contactor is a normal open type high-current contactor, thesaid DCDC converting unit includes the DCDC converter and high-powerdiode connecting with it.

The said fuel cell system connects the said DCDC converting unit,contactor, power supply output end, the said controller connects thesaid fuel cell system, operation control unit, contactor, the saidenergy storage device connects the said controller, operation controlunit and contactor.

Preferably, the said fuel cell system, energy storage device, DCDCconverting unit are installed in proper order on the base plate of thesaid enclosure along the said enclosure in a direction from front toback.

Preferably, the installation positions of both the said operationcontrol unit 6 and controller are higher than that of the said DCDCconverting unit and energy storage device.

Preferably, the said operation control unit and controller are installedin proper order along the said enclosure in a direction from front toback.

Preferably □the said contactor is installed in the area located betweenthe side board of the said enclosure and the said energy storage deviceon the said base plate.

Preferably, the electric isolation board, the hydrogen storage system,the filling valve provided in the said enclosure are also included, thesaid electric isolation board divides the space of the said enclosureinto an electronic system space and a gas supply space, the said fuelcell system, DCDC converting unit, contactor, energy storage device,controller, operation control unit are located in the said electronicsystem space, the said hydrogen storage system, filling valve arelocated in the said gas supply space, the said gas supply space islocated on one side of the said electronic system space.

Preferably, the output end of the fuel cell that the said fuel cellsystem contains connects the input end of the said DCDC converting unit,the DCDC converting unit connects through the said contactor the saidenergy storage device, the output end of the said DCDC converting unitalso connects the said power supply output end and the high-powerauxiliary component that the said fuel cell system contains, the port ofthe said energy storage device connects through the said contactor thesaid power supply output end and the high-power auxiliary component thatthe said fuel cell system contains, the said operation control unitconnects respectively the said energy storage device, DCDC convertingunit, controller, the said controller connects respectively the fuelcell that the said fuel cell system contains, auxiliary system, DCDCconverting unit, the control end of contactor, the energy storagedevice, in which the said auxiliary system includes the said high-powerauxiliary component.

The said operation control unit is used to receive operation signals andsupplies power for the said controller and DCDC converting unit, thesaid controller is used to receive the operation instructions generatedby the said operation control unit according to the said operationsignals and control according to the said operation instructions thesaid contactor, DCDC converting unit, auxiliary system, the saidcontroller is also used to measure the state parameters of the fuel cellthat the said fuel cell system contains, measure the state parameters ofthe said energy storage device, measure the state parameters of the saidauxiliary system and receive the state data of the said DCDC convertingunit.

Preferably, the output end of the said fuel cell connects the input endof the said DCDC converter, the positive pole of the output end of thesaid DCDC converter connects the positive pole of the said high-powerdiode, the negative pole of the said high-power diode connects throughthe said contactor the said energy storage device, the said DCDCconverter connects the said controller and is controlled by the saidcontroller, the said DCDC converter connects the said operation controlunit and receives power supplied by the said operation control unit.

Preferably, the said operation control unit changes the electricconnection state with the said DCDC converting unit and controlleraccording to the startup operation signal received.

Preferably, the state data of the said DCDC converting unit include DCDCinput current, DCDC input voltage.

Preferably, any one or more types of following devices are alsoincluded:

-   -   Hydrogen safety system, the said hydrogen safety system include        the sensors placed respectively in the electronic control system        space and gas supply space, the said sensors connect the said        controller,    -   Monitoring display, with the said monitoring display connecting        the said controller,    -   ON and OFF button, with the said ON and OFF button 92 connecting        respectively the said operation control unit 6 and controller,    -   Remote control, the said remote control connecting in a radio        mode the said operation control unit,    -   Emergency stop button, with the said emergency stop button        connecting the said operation control unit.

Comparing with the existing technology, the said forklift fuel cellsupply system has the following beneficial effects:

1) The energy storage device placed by the existing technology in thesystem is small in capacity, making the energy storage device be in acharging and discharging condition with a high multiplying factor andreducing the service life of the energy storage device. The saidforklift fuel cell supply system can contain an energy storage devicewith a higher capacity, making the energy storage device be in acharging and discharging condition with a low multiplying factor andextending the service life of the energy storage device and the time forwhich the system can be left unused. For example, in the circumstancethat what is placed in the energy storage device is a lithium ionbattery, the lithium ion battery placed as designed by the existingtechnology has a capacity 32 AH, a peak output 48 KW. The lithium ionbattery that can be placed in the forklift fuel cell supply system has acapacity 50 AH, a peak output 72 KW. When absorbing the forklift brakingat 600 A, the charging multiplying factor is 12C. That value in theexisting technology is 18C. A higher energy storage device capacityreduces the charging and discharging multiplying factor at the samecurrent output and favors extension of battery service life.

2) The said forklift fuel cell supply system is compact in structure andfacilitates such work as system installation, overhaul and maintenance,etc.

3) In the enclosure, the operation control unit, controller are placedon the top. In the circumstance when they are not used by the system andmoved outside forklift, inspection and maintenance, failure recovery canbe made. The controller control software upgrading is also facilitated.

4) Spaces are reserved between parts and components, parts andcomponents and enclosure, which facilitates line connection, part andcomponent removal.

5) The compact structural design of the said forklift fuel cell supplysystem allows placing of the emergency stop button. In case of anyemergency, the whole system can be disconnected quickly.

6) Such components as ON and OFF button, emergency stop button, fillingvalve, etc. required by system operation are placed at appropriateheights to facilitate filling, operation.

BRIEF DESCRIPTION OF THE DRAWINGS

By reading and referring to the detailed descriptions made to thenon-restrictive embodiment examples by the following attached figures,other characteristics, purposes and advantages of this invention willbecome more evident:

FIG. 1 is the schematic diagram of the general structure of forkliftfuel cell supply system;

FIG. 2 is the schematic diagram of the structure of the fuel cell supplysystem according to this invention;

FIG. 3 is the specific structural schematic diagram of the DCDCconverting unit in the compact type fuel cell supply system as shown inFIG. 2;

FIG. 4 shows the schematic diagram of the high-power diode position inthe compact type fuel cell supply system of a preferable case of thefirst embodiment example provided according to this invention;

FIG. 5 is embodiment A of forklift fuel cell supply system;

FIG. 6 is embodiment B for forklift fuel cell supply system;

DETAILED DESCRIPTION

A detailed description to this invention is to be made below bycombining with specific embodiment examples. The following embodimentexamples will help the technical personnel in this field furtherunderstand this invention, but it does not limit this invention in anyform. It should be pointed out that for ordinary technical people inthis field, adjustments and changes can also be made under theprerequisite of not being divorced from the conceiving of thisinvention. All these belong to the protection scope of this invention.

The said forklift fuel cell supply system consists of enclosure 90 andthe fuel cell system 100, DCDC converting unit 2, contactor 3, energystorage device 4, controller 7, operation control unit 6, electricisolation board 901, hydrogen storage system, filling valve 95 providedin the said enclosure 90, which also consists of the power supply outputend 5 provided outside the said enclosure 90. In which, the saidcontactor 3 is a normal open type high-current contactor, the said DCDCconverting unit 2 includes the DCDC converter 21 and high-power diode 22connecting with it. The said fuel cell system 100 connects the said DCDCconverting unit 2, contactor 3, power supply output end 5, the saidcontroller 7 connects the said fuel cell system 100, operation controlunit 6, contactor 3, the said energy storage device 4 connects the saidcontroller 7, operation control unit 6, contactor 3.

The said fuel cell system 100, energy storage device 4, DCDC convertingunit 2 are installed in proper order on the base plate of the saidenclosure 90 along the said enclosure 90 in a direction from front toback. The installing positions of both the said operation control unit 6and controller 7 are higher than that of the said DCDC converting unit 2and energy storage device 4. The said operation control unit 6 andcontroller 7 are installed in proper order along the said enclosure 90in a direction from front to back. The said contactor 3 is installed inthe area located between the side board of the said enclosure 90 and thesaid energy storage device 4 on the said base plate.

The said electric isolation board 901 divides the space of the saidenclosure 90 into electronic system space and gas supply space, the saidfuel cell system 100, DCDC converting unit 2, contactor 3, energystorage device 4, controller 7, operation control unit 6 are locatedinside the said electronic system space, the said hydrogen storagesystem, filling valve 95 are located in the said gas supply space, thesaid gas supply space is located on one side of the said electronicsystem space.

In a preferable case, the said forklift fuel cell supply system alsoconsists of hydrogen safety system, monitoring display 91, ON and OFFbutton 92, remote control 93, emergency stop button 94, in which thesaid hydrogen safety system consists of the sensors placed respectivelyin the electronic control system space and gas supply space, the saidsensors connect the said controller 7, the said monitoring display 91connects the said controller 7, the said ON and OFF button 92 connectsrespectively the said operation control unit 6 and controller 7, thesaid remote control 93 connects in a radio mode the said operationcontrol unit 6, the said emergency stop button 94 connects the saidoperation control unit 6.

The said fuel cell system 100 consists of fuel cell 1 and auxiliarysystem 8. The said auxiliary system 8 consists of air supply system,cooling system, hydrogen system, the said high-power auxiliary component80 refers to a high-power component in the auxiliary system (forexample, fan, pump, heat dissipation fan). The technical people in thisfield can refer to the existing technology to accomplish the saidauxiliary system 8 and its high-power auxiliary component 80. Nounnecessary detail is to be given here.

FIG. 5 and FIG. 6 show the fuel cell supply systems in the twoembodiments according to the said forklift fuel cell supply system.Specifically, FIG. 5 shows embodiment A-1: the 2-ton electric forkliftfrom a forklift plant uses Model 9PZS630 48V lead-acid battery. Thatlead-acid battery is 1,070 mm long, 827 mm wide, 520 mm high, weighs1,070 kg with a voltage 48V. The working voltage range of the forkliftis 40-60V. The system is designed to have a length 980 mm, a width 827mm, a height 520 mm and a weight 1,070 Kg, the rated voltage of thesystem is 40-60V. FIG. 6 shows embodiment A-2: the four-wheelcounterbalanced type forklift from a forklift plant using lead-acidbattery is 982 mm long, 836 mm wide, 565 mm high and weighs 1,400 kg.The working voltage range of the forklift is 40-60V. The system isdesigned to have a length 980 mm, a width 827 mm, a height 565 mm and aweight 1400 Kg. The rated voltage of the system is 40-60V. Being similarto embodiment A, it has a counterweight layer added on the bottom toreach the required forklift weight.

The reason that a compact structure as shown in FIG. 1 can be designedfor the said forklift fuel cell supply system is mainly due to adoptingthe compact type fuel cell supply system as shown in FIG. 2.

FIG. 2 is the schematic diagram of the structure of the compact typefuel cell supply system of the first embodiment example providedaccording to this invention, in this embodiment example, the saidcompact type fuel cell supply system consists of fuel cell 1, DCDCconverting unit 2, contactor 3, energy storage device 4, power supplyoutput end 5, operation control unit 6, controller 7, auxiliary system8, in which the said contactor 3 is a normal open type high-currentcontactor, the said DCDC converting unit 2 includes DCDC converter 21and high-power diode 22 connecting with it.

Specifically, the output end of the said fuel cell 1 connects the inputend of the said DCDC converting unit 2, DCDC converting unit 2 connectsthrough the said contactor 3 the said energy storage device 4, theoutput end of the said DCDC converting unit 2 also connects the saidpower supply output end 5 and the high-power auxiliary component 80 thatthe said auxiliary system 8 contains, the port of the said energystorage device 4 connects through the said contactor 3 the said powersupply output end 5 and auxiliary system 8, the said operation controlunit 6 connects respectively the said energy storage device 4, DCDCconverting unit 2, controller 7, the said controller 7 connectsrespectively the said fuel cell 1, DCDC converting unit 2, the controlend of contactor 3, energy storage device 4 and auxiliary system 8.

In this embodiment example, the positive pole of the output end of thesaid DCDC converting unit 2 connects through the said contactor 3 thepositive pole of the said energy storage device 4, the negative pole ofthe output end of the said DCDC converting unit 2 connects through thesaid contactor 3 the negative pole of the said energy storage device 4,the positive pole of the said energy storage device 4 connects throughthe said contactor 3 the positive pole of the said power supply outputend 5 and the positive pole of auxiliary system 8, the negative pole ofthe said energy storage device 4 connects directly the negative pole ofthe said power supply output end 5 and the negative pole of auxiliarysystem 8; and in a variation of this embodiment example, the differencefrom the first embodiment example as shown in FIG. 2 is that in thisvariation, the change of the said contactor 3 in connecting position is:the said contactor 3 is connected between the negative pole of theoutput end of the said DCDC converting unit 2 and the negative pole ofthe said energy storage device 4, and the positive pole of the outputend of the said DCDC converting unit 2 and the positive pole of the saidenergy storage device 4 are connected directly between them,correspondingly, the positive pole of the said energy storage device 4connects directly the positive pole of the said power supply output end5 and the positive pole of auxiliary system 8, the negative pole of thesaid energy storage device 4 connects through the said contactor 3 thenegative pole of the said power supply output end 5 and the negativepole of auxiliary system 8. The technical people in this fieldunderstand that the two connection modes for contactor 3 as described inthis natural paragraph can both realize “DCDC converting unit 2connecting through the said contactor 3 the said energy storage device4” and “the port of the said energy storage device 4 connecting throughthe said contactor 3 the said power supply output end 5 and auxiliarysystem 8”.

The said auxiliary system 8 consists of air supply system, coolingsystem, hydrogen system, hydrogen safety system, the said high-powerauxiliary component 80 refers to a high-power component in the auxiliarysystem (for example, fan, pump, heat dissipation fan). The technicalpeople in this field can refer to the existing technology to accomplishthe said auxiliary system 8 and its high-power auxiliary component 80.No unnecessary detail is to be given here.

The said operation control unit 6 is used to receive operation signalsand supplies power for the said controller 7 and DCDC converting unit 2,the said controller 7 is used to receive the operation instructionsgenerated by the said operation control unit 6 according to the saidoperation signals and control according to the said operationinstructions the said contactor 3, DCDC converting unit 2, auxiliarysystem 8, the said controller 7 is also used to measure the stateparameters of the said fuel cell 1, measure the state parameters of thesaid energy storage device 4, measure the state parameters of the saidauxiliary system 8 and receive the state data of the said DCDCconverting unit 2. The said DCDC converter 21 consists of CANcommunication module, input voltage measurement module, input currentmeasurement module, output voltage measurement module, output currentmeasurement module. Preferably, DCDC converter 21 can control accordingto the communication data of the CAN communication module the specificnumerical values of the output current, voltage; also outputs throughthe CAN communication module such data as input voltage, input current,output voltage, output current, etc. The state data of the said DCDCconverting unit 2 includes DCDC input current, DCDC input voltage.

The said controller 7 is a controller with an integrated design, whichis equivalent to the scattered fuel cell controller, whole vehiclecontroller, battery energy management system in the invention patentapplication of China with patent application number “200610011555.1”;further specifically, the said controller 7 can consist of energymanagement unit, fuel cell control unit, energy storage devicemonitoring unit, hydrogen safety monitoring unit, system failuremonitoring unit and startup control unit.

More specifically, as shown in FIG. 3, the output end of the said fuelcell 1 connects the input end of the said DCDC converter 21, thepositive pole of the output end of the said DCDC converter 21 connectsthe positive pole of the said high-power diode 22, negative pole of thesaid high-power diode 22 connects through the said contactor 3 the saidenergy storage device 4, the said DCDC converter 21 connects the saidcontroller 7 and is controlled by the said controller 7, the said DCDCconverter 21 connects the said operation control unit 6 and receives thepower supplied by the said operation control unit 6. And in a variationof this embodiment example, the difference from the first embodimentexample as shown in FIG. 3 is that in this variation, the positive poleof the output end of the said fuel cell 1 connects the positive pole ofthe said high-power diode 22, the negative pole of the said high-powerdiode 22 connects the positive pole of the input end of the said DCDCconverter 21, the negative pole of the output end of the said fuel cell1 connects directly the negative pole of the input end of the said DCDCconverter 21, the output end of the said DCDC converter 21 directlyconnects through the said contactor 3 the said energy storage device 4.

Further, in this embodiment example, the said compact type fuel cellsupply system also consists of monitoring display 91, ON and OFF button92, remote control 93, emergency stop button 94, in which the saidmonitoring display 91 connects the said controller 7, the said ON andOFF button 92 connects respectively the said operation control unit 6and controller 7, the said remote control 93 connects in a radio modethe said operation control unit 6, the said emergency stop button 94connects the said operation control unit 6. As shown in FIG. 1, when thesaid ON and OFF button 92 or remote control 93 gives a startup signal,the said operation control unit 6 supplies power to the said controller7, the said controller 7 outputs a control signal to the contactor usedas a switch to make it close, the said energy storage device 4 suppliespower through the said contactor 3 to the said high-power auxiliarycomponent 80, in the said auxiliary system 8, except the said high-powerauxiliary component 80, other devices (for example, hydrogen system,hydrogen safety system) are supplied by the said controller 7, at thesame time, the said controller 7 outputs signals to all modulesconstituting the said auxiliary system 8 to start the said fuel cell 1;after starting, the said contactor 3 maintains the state of connectionat all times. By adopting this starting mode, it is not necessary to useadditionally configured auxiliary battery and auxiliary DC/DC converterfor charging, as a result, parts and components and corresponding linesare reduced, system reliability is improved, space is saved, systemvolume and costs are reduced.

In a preferable case of this embodiment example, as shown in FIG. 4, thesaid high-power diode 22 is placed on the heat dissipation passage ofthe said DCDC converter 21, this can use the air discharged from the airduct 2101 by the heat dissipation fan 2102 contained by the said DCDCconverter itself to dissipate heat from the said high-power diode 22, asa result, the heat dissipation fan on the heat dissipater 2201 (i.e.aluminum fin) for the said high-power diode is saved, the volume of heatdissipater is reduced, energy is saved, at the same time, the line tosupply power to that heat dissipation fan is also saved. The saidoperation control unit 6 changes the electric connection state with thesaid DCDC converting unit and controller 7 according to the startupoperation signal received. Thus, the said controller 7 is in anoperation condition only when the system is working and will not lead tothe problem of high system energy consumption due to being always in anoperation condition.

Next, the system working principle is described through a preferableembodiment of this invention. Specifically, When the system is notstarted, the said operation control unit 6 and the said controller 7,DCDC converting unit 2 establish no electric connection state betweenthem. When the button of the said remote control 93 or the said ON andOFF button 92 is depressed, the said operation control unit 6 and thesaid controller 7, DCDC converting unit 2 establish an electricconnection between them, the said energy storage device 4 supplies powerthrough the said operation control unit 6 to the said controller 7, theoutput signal of the said controller 7 drives the said contactor 3 toget connected, the said energy storage device 4 supplies power throughthe said contactor 3 to the said high-power auxiliary component 80, inthe said auxiliary system 8, except the said high-power auxiliarycomponent 80, other devices (for example, hydrogen system, hydrogensafety system) are supplied by the said controller 7, at the same time,the said controller 7 outputs working signals to all modulesconstituting the said auxiliary system 8 to start the said fuel cell 1;the said fuel cell 1 outputs power to the said DCDC converting unit 2,the said controller 7 controls according to the received state datasignals of the said fuel cell 1, energy storage device 4, DCDCconverting unit 2 the said DCDC converting unit 2 output current; underthe normal system working condition, the output voltage of the said DCDCconverting unit 2 is higher than the output voltage of the said energystorage device 4, the output current of the said DCDC converting unit 2is output through the said power supply output end 5 to the smallvehicle drive system carrying the said fuel cell supply system to drivethe small vehicle to work, at the same time, the said DCDC convertingunit 2 charges the said energy storage device 4, supplies power to thesaid high-power auxiliary component 80, operation control unit 6; when asmall vehicle is in a high-power driving condition, the said powersupply output end 5 needs to output high power, high currency, at thistime, the said DCDC converting unit 2 output current is not sufficientto satisfy the requirements, the said energy storage device 4 willoutput current together with the said DCDC converting unit 2 to thesmall vehicle driving system carrying that fuel cell supply systemthrough the said power supply output end 5 to drive that small vehicleto maintain the high-power driving condition; when the small vehicle isin a braking condition, the power energy recovered by the brake chargesthrough the power supply output end the energy storage device.

When it is necessary to start the system, just depress the button of thesaid remote control 93 or the said ON and OFF button 92, in the meantimethat the said operation control unit 6 and the said controller 7, DCDCconverting unit 2 establish an electric connection, the said operationcontrol unit 6 outputs a switch signal to the said controller 7, thesaid controller 7, after receiving the switch signal, outputs a signalto maintain power supply to the said operation control unit 6, so thatthe said operation control unit 6 and the said controller 7, DCDCconverting unit 2 maintain an electric connection state; at the sametime, the said controller 7 also drives the indicator light of the saidON and OFF button 92 to become on to prompt system starting; at thistime, the button of the said remote control 93 or the said ON and OFFbutton 92 can be released.

When it is necessary to close the system, depress again the button ofthe said remote control 93 or the said ON and OFF button 92, the saidoperation control unit 6 outputs a switch signal to the said controller7, the said controller 7, after receiving the switch signal, controlsthe indicator light of the said ON and OFF button 92 to blink (promptingswitching off, at this time, the button of the said remote control 93 orthe said ON and OFF button 92 can be released), the said controller 7simultaneously controls the said auxiliary system 8 to stop working, andthen stops outputting the signal to maintain power supply to the saidoperation control unit 6, so that the electric connection of the saidoperation control unit 7 and the said controller 7, DCDC converting unit2 is disconnected; the whole system stops working.

When the said emergency stop button 94 is depressed, the electricconnection between the said operation control unit 6 and the saidcontroller 7, DCDC converting unit 2 get disconnected quickly to cut offthe power supply to the whole system and make the system stop working.

The said monitoring display 91 gets power, communication data from thesaid controller 7, displays the system condition, failure information,etc. on the screen.

The embodiment examples of this invention are described above. Whatneeds understanding is that that this invention is not limited to abovespecific embodiments. The technical people in this field can makevarious variations or modifications with the Claim, and this does notinfluence the essential contents of this invention.

1. A forklift fuel cell supply system consists of enclosure 90 and thefuel cell system 100, DCDC converting unit 2, contactor 3, energystorage device 4, controller 7 provided in the said enclosure 90, whichalso consists of the power supply output end 5 provided outside the saidenclosure 90 and the operation control unit 6 provided in the saidenclosure 90, in which the said contactor 3 is a normal open typehigh-current contactor, the said DCDC converting unit 2 includes theDCDC converter 21 and high-power diode 22 connecting with it, The saidfuel cell system 100 connects the said DCDC converting unit 2, contactor3, power supply output end 5, the said controller 7 connects the saidfuel cell system 100, operation control unit 6, contactor 3, the saidenergy storage device 4 connects the said controller 7, operationcontrol unit 6 and contactor
 3. 2. According to claim 1, the said fuelcell system 100, energy storage device 4, DCDC converting unit 2 areinstalled in proper order on the base plate of the said enclosure 90along the said enclosure 90 in a direction from front to back. 3.According to claim 1, the installation positions of both the saidoperation control unit 6 and controller 7 are higher than that of thesaid DCDC converting unit 2 and energy storage device
 4. 4. According toclaim 1, the said operation control unit 6 and controller 7 areinstalled in proper order along the said enclosure 90 in a directionfrom front to back.
 5. According to claim 1, the said contactor 3 isinstalled in the area located between the side board of the saidenclosure 90 and the said energy storage device 4 on the said baseplate.
 6. According to claim 1, the electric isolation board 901, thehydrogen storage system, the filling valve 95 provided in the saidenclosure 90 are also included, the said electric isolation board 901divides the space of the said enclosure 90 into an electronic systemspace and a gas supply space, the said fuel cell system 100, DCDCconverting unit 2, contactor 3, energy storage device 4, controller 7,operation control unit 6 are located in the said electronic systemspace, the said hydrogen storage system, filling valve 95 are located inthe said gas supply space, the said gas supply space is located on oneside of the said electronic system space.
 7. According to claim 1, theoutput end of the fuel cell 1 that the said fuel cell system 100contains connects the input end of the said DCDC converting unit 2, theDCDC converting unit 2 connects through the said contactor 3 the saidenergy storage device 4, the output end of the said DCDC converting unit2 also connects the said power supply output end 5 and the high-powerauxiliary component 80 that the said fuel cell system 100 contains, theport of the said energy storage device 4 connects through the saidcontactor 3 the said power supply output end 5 and the high-powerauxiliary component 80 that the said fuel cell system 100 contains, thesaid operation control unit 6 connects respectively the said energystorage device 4, DCDC converting unit 2, controller 7, the saidcontroller 7 connects respectively the fuel cell that the said fuel cellsystem 100 contains, auxiliary system 8, DCDC converting unit 2, thecontrol end of contactor 3, the energy storage device 4, in which thesaid auxiliary system 8 includes the said high-power auxiliary component80, the said operation control unit 6 is used to receive operationsignals and supplies power for the said controller 7 and DCDC convertingunit 2, the said controller 7 is used to receive the operationinstructions generated by the said operation control unit 6 according tothe said operation signals and control according to the said operationinstructions the said contactor 3, DCDC converting unit 2, auxiliarysystem 8, the said controller 7 is also used to measure the stateparameters of the fuel cell 1 that the said fuel cell system 100contains, measure the state parameters of the said energy storage device4, measure the state parameters of the said auxiliary system and receivethe state data of the said DCDC converting unit
 2. 8. According to claim1, the output end of the said fuel cell 1 connects the input end of thesaid DCDC converter 21, the positive pole of the output end of the saidDCDC converter 21 connects the positive pole of the said high-powerdiode 22, the negative pole of the said high-power diode 22 connectsthrough the said contactor 3 the said energy storage device 4, the saidDCDC converter 21 connects the said controller 7 and is controlled bythe said controller 7, the said DCDC converter 21 connects the saidoperation control unit 6 and receives power supplied by the saidoperation control unit
 6. 9. According to claim 1, the said operationcontrol unit 6 changes the electric connection state with the said DCDCconverting unit and controller 7 according to the startup operationsignal received.
 10. According to claim 1, the state data of the saidDCDC converting unit 2 include DCDC input current, DCDC input voltage.11. According to claim 1, any one or more types of following devices arealso included: Hydrogen safety system, the said hydrogen safety systeminclude the sensors placed respectively in the electronic control systemspace and gas supply space, the said sensors connect the said controller7; Monitoring display 91, with the said monitoring display 91 connectingthe said controller 7, ON and OFF button 92, with the said ON and OFFbutton 92 connecting respectively the said operation control unit 6 andcontroller 7; Remote control 93, the said remote control 93 connectingin a radio mode the said operation control unit 6; and Emergency stopbutton 94, with the said emergency stop button 94 connecting the saidoperation control unit 6.